The Red Devils are thought to be on the lookout for a number of new signings as the deadline for Premier League incoming transfers approaches.
Mina has emerged as a potential target for the Red Devils in recent weeks as Jose Mourinho looks to try and bolster his defensive options ahead of the close of the transfer window on Thursday afternoon.
The 23-year-old Colombia international has also been touted as a target for Everton in recent days as the speculation about his future at Camp Nou continues.
However, Sunday Times reporter has now claimed that Mina would much prefer a move to Old Trafford, but a deal has not yet been agreed between the two clubs.
Speaking on the Transfer Window podcast, Castles said: “He would definitely prefer to go to Man United over Everton.
“Man United have some issues with the agent fees involved. They haven’t fully agreed.”
Manchester United will be looking to challenge for the Premier League title next season after they finished second and without a trophy last term.
The Red Devils are aiming to win the Premier League trophy for the first time since their final triumph under Sir Alex Ferguson back in 2013.
Manchester United will get the new Premier League season under way when they host Leicester City at Old Trafford on Friday night.
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